Specifications For Fairchild Fairbug Data Files - Data I/O 298 Manual

Address specification is required for only the first data byte
in the transfer. An address must have 1 to 4 hex
characters and be followed by a space. The programmer
records the next hex character after the space as the start
of the first data byte. (A carriage return must follow the
space if the start code
?M
is used.) Succeeding bytes are
recorded sequentially.
Each data record is followed by a comma if the next record
is not preceded by an address, or by a semicolon if it starts
with an address. Records consist of data bytes expressed
as two hexadecimal characters and followed by either a
comma or semicolon, and a carriage return. Any characters
received between a comma or semicolon and a carriage
return will be ignored by the programmer.
The carriage-return character is significant to this format
because it can signal either the continuation or the end of
data flow; if the carriage return is preceded by a comma or
semicolon, more data must follow; the absence of a
comma or semicolon before the carriage return indicates
the end of transmission.
Output data records are followed by either a comma or a
semicolon and a carriage return. The Start-of-File records
are expressed exactly as for input.
INPUT
DATA RECORD
x
H
H
H
H
H
START CHARACTER
HH = One data byte in hexadecimal notation
NOTE:
There are always 8 data bytes per record in FS Format
C C =Checksum. One-digit summation of data in record
OUTPUT
NOTES
1) Output always has 8 data bytes per record.
2) Each line ends with nonprinting line feed, carriage return
and nulls.
2 Hex characters= 1 byte Data Records
SAAAA \ , /
XHHHHHHHHHHHHHHHHC
~
XHHHHHHHHHHHHHHHHC
SA AAA
XHHHHHHHHHHHHHHHHC
*
• FAIRCHILD FAIRBUG, CODE 80
In the Fairbug format, input and output requirements are
identical; both have 8-byte records and identical control
characters. Figure A-9 simulates a Fairbug data file. A file
begins with a 5-character prefix and ends with a one-
character suffix. The Start-of-File character is an "S",
followed by the address of the first data byte. Each data
byte is represented by 2 hexadecimal characters.
NOTE
Address specification is optional in this
format; a record with no address directly
follows the previous record.
A 1-digit hexadecimal checksum follows the data in each
data record. The checksum represents, in hexadecimal
notation, the sum of the binary equivalents of the 16 digits
in the record; the half carry from the fourth bit is ignored.
The programmer ignores any character (except for address
characters) between a checksum and the start character of
the next data record. These spaces can be used for any
comments.
The last record consists of an asterisk only, which indicates
the end of data transmission.
START-OF.FILE RECORD
s
A
A
A
A
START CHARACTER
AA.AA= Address of first data byte
in
file. AAAA in
hexadecimal notation only
END·OF·FILE RECORD
LEGEND
S =START CHARACTER
AAAA = Address Field
X = Data-Record Start Character
HH = Two Hexadecimal Digits (0-9, A·F)
C =Checksum
Figure A-9. Specifications for Fairchild Fairbug Data Files
A-8
10-990-0013